Method of controlling connection between nodes in digital interface

ABSTRACT

A method of controlling connection between nodes in a digital interface whereby a first node that is a master node determines a second node to be the master and controls a point-to-point connection or a broadcast connection to another node. The first node having the display device determines the second node to be the master in accordance with a user selection, and transmits a connection command of a predetermined format for transmitting a data stream to the second node. The second node determined as the master in accordance with the transmitted connection command of the predetermined format is allocated with a channel and a bandwidth from an isochronous resource manager (IRM), and performs a point-to-point connection between the second node and the first node to transit the data stream. Thus, the transmission/reception, reproduction, and control of the data stream of the program can be smoothly performed.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a continuation of prior U.S. application Ser. No.11/451,444, filed Jun. 13, 2006, now U.S. Pat. No. 7,289,482, which is acontinuation of U.S. application Ser. No. 09/644,301, filed Aug. 23,2000, now U.S. Pat. No. 7,068,674, which claims priority to Korea SerialNo. P1999-35030 filed on Aug. 23, 1999. The disclosures of the priorapplications are considered part of (and are incorporated by referencein) the disclosure of this application.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates generally to a digital interface, and moreparticularly to a method of controlling connection between nodes in adigital interface.

2. Description of the Related Art

FIG. 1 illustrates a connection state of a conventional 1394 systemconnected between nodes. Referring to FIG. 1, the conventional digitalinterface includes first and second input plug control registers 21 and22 for inputting/outputting connection information between nodesconnected to a 1394 serial bus 10 in accordance with control signals ofan application node (not illustrated), a first audio/video node 20comprising a first input master plug register 23, a third input plugcontrol register 31 for inputting/outputting connection informationbetween nodes connected to the 1394 serial bus 10 in accordance withcontrol signals of the application node, a second audio/video node 30comprising a second input master plug register 32, a fourth input plugcontrol register 41 for inputting/outputting connection informationbetween nodes connected to the 1394 serial bus 10 in accordance withcontrol signals of the application node, a third video/audio node 40comprising a third input master plug register 42, fifth and sixth plugcontrol registers 51 and 52 for inputting/outputting connectioninformation between nodes connected to the 1394 serial bus 10 inaccordance with control signals of the application node, a fourthaudio/video node 50 comprising a fourth input master plug register 53,an output plug control register 61 for inputting/outputting connectioninformation between nodes connected to the 1394 serial bus 10 inaccordance with control signals of the application node, and a fifthaudio/video node 60 comprising an output master plug register 62.

The method of controlling connection between nodes for the conventionaldigital interface as constructed above will be explained in detail withreference to accompanying drawings.

The application node is allocated with a channel for transmittingisochronous data from the fifth audio/video node 60 to the firstaudio/video node 20 through a point-to-point connection or broadcastconnection, and writes in the same format the output plug controlregister in the fifth audio/video node 60 and the input plug controlregister in the first audio/video node 20 in the output plug controlregister 61 and the second input plug control register 22.

Thereafter, the application node writes “1” in an on-line bit of theoutput plug control register 61 in the fifth audio/video node 60 and anon-line bit of the second input plug control register 22 to transmit theisochronous data.

Also, the application node writes in the same format the output plugcontrol register in a point-to-point connection counter or a broadcastconnection counter of the output plug control register 61 in the fifthaudio/video node 60.

Then, the isochronous data is transmitted from the fifth audio/videonode 60 to the first audio/video node 20 through the channel.

Thus, transmission of the isochronous data from the fifth audio/videonode 60 to the second and fourth audio/video nodes 30 and 40 isperformed through the above-described process.

According to the conventional method of controlling connection betweennodes in a digital interface, however, since no command for connectionthe nodes to the digital interface is provided, thetransmission/reception, reproduction and control of a data stream of apredetermined program cannot be smoothly performed.

SUMMARY OF THE INVENTION

Accordingly, the present invention is directed to a method ofcontrolling connection between nodes in a digital interface thatsubstantially obviates one or more of the problems due to limitationsand disadvantages of the related art.

An object of the present invention is to provide a method of controllingconnection between nodes in a digital interface whereby a first nodethat is a master node determines a second node as a master, and apoint-to-point connection or a broadcast connection to another thirdnode is controlled through the second node.

Additional features and advantages of the invention will be set forth inthe description which follows, and in part will be apparent from thedescription, or may be learned by practice of the invention. Theobjectives and other advantages of the invention will be realized andattained by the structure particularly pointed out in the writtendescription and claims thereof as well as the appended drawings.

To achieve these and other advantages and in accordance with the purposeof the present invention, as embodied and broadly described, the methodof controlling connection between nodes in a digital interface comprisesthe steps of a first node that is a master having a display devicedetermining a second node to be a master in accordance with a userselection and transmitting a connection command of a predeterminedformat for transmitting a data stream, and the second node determined asthe master in accordance with the transmitted connection command of thepredetermined format being allocated with a channel and a bandwidth froman isochronous resource manager (IRM), performing a point-to-pointconnection between the second node and the first node, and transmittingthe data stream.

The connection command of the predetermined format may be composed of asubfunction region representing whether the connection is thepoint-to-point connection or a broadcast connection, a connection regionrepresenting whether to make or cut off the connection, a source nodeidentification (ID) region representing a source node ID of the nodewhich transmits the data stream, and a destination node ID regionrepresenting a destination node ID of the node which receives the datastream.

The subfunction region may be set to the broadcast connection from thesecond node to the first node or another node to enable the transmissionof the data stream.

At the data stream transmitting step, the second node may transmit aresponse of a predetermined format which corresponds to the connectioncommand of the predetermined format to the first node.

The format of the response may be the same as the format of theconnection command.

The format of the response may further include a bandwidth regionrepresenting a bandwidth allocated from the source node, a sourcechannel number region representing a source channel number allocatedfrom the source node, an output plug control register number regionrepresenting an output plug control register (PCR) number of the sourcenode, a destination channel number region representing a destinationchannel number of the destination node for receiving the data stream,and an input PCR number region representing an input PCR number of thedestination node.

According to another aspect of the present invention, the first nodethat is the master having the display device determines the second nodeto be the master in accordance with the user selection to perform thepoint-to-point connection to a third node, and transmits the connectioncommand of the predetermined format for transmitting the data stream.The second node is allocated with the channel and the bandwidth from theisochronous resource manager (IRM), and then performs the point-to-pointconnection between the second node itself and the third node to enabletransmission of the data stream.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are included to provide a furtherunderstanding of the invention and are incorporated in and constitute apart of this specification, illustrate embodiments of the invention andtogether with the description serve to explain the principles of theinvention:

In the drawings:

FIG. 1 is a view illustrating a connection state of a conventional 1394system connected between nodes.

FIG. 2 is a block diagram illustrating the construction of a system towhich the method of controlling connection between nodes in a digitalinterface according to an embodiment of the present invention isapplied.

FIGS. 3 a and 3 b are views illustrating a connection command formaccording to the method of controlling connection between nodes in adigital interface according to an embodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Reference will now be made in detail to the method of controllingconnection between nodes in a digital interface according to a preferredembodiment of the present invention, examples of which are illustratedin the accompanying drawings.

FIG. 2 is a block diagram illustrating the construction of a system towhich the method of controlling connection between nodes in a digitalinterface according to an embodiment of the present invention isapplied. The system comprises a digital television (DTV) 101, a set-topbox (STB) 102, and a digital video disk (DVD) player 103, and a disk104.

FIGS. 3 a and 3 b are views illustrating a connection command formaccording to the method of controlling connection between nodes in adigital interface according to an embodiment of the present invention.As shown in FIG. 3 a, the connection command is composed of asubfunction region representing whether the connection is apoint-to-point connection or a broadcast connection, a connection regionrepresenting whether to make or cut off the connection, a source nodeidentification (ID) region representing a source node ID of the nodewhich transmits a data stream, and a destination node ID regionrepresenting a destination node ID of the node which receives the datastream, a bandwidth region representing a bandwidth allocated from thesource node, a source channel number region representing a sourcechannel number allocated from the source node, an output plug controlregister number region representing an output plug control register(PCR) number of the source node, a destination channel number regionrepresenting a destination channel number of the destination node forreceiving the data stream, and an input PCR number region representingan input PCR number of the destination node. The subfunction region inFIG. 3 a is illustrated in detail in FIG. 3 b.

The method of controlling connection between nodes in a digitalinterface as constructed above will be explained in detail withreference to the accompanying drawings.

First, if a user selects the DTV 101 or the STB 102 which are displayedon a screen in order to view a specified program received in the STB 102through an IEEE 1394 cable as shown in FIG. 2, the DTV 101 transmits theconnection command of a predetermined format as shown in FIGS. 3 a and 3b to the STB 102 with the STB 102 determined as a master to transmit thedata stream.

Specifically, before transmitting the connection command to the STB 102,the DTV 101 writes “0x01” in the subfunction region of the connectioncommand as shown in FIGS. 3 a and 3 b to record the point-to-pointconnection, “0x00” in the connection region to record making of theconnection, the node ID of the STB 102 in the source node ID region, andits own ID in the destination node ID region, respectively.

The node IDs of the nodes displayed on the screen are connected to theIEEE 1394 cable, and are stored in the DTV 101 when the power is turnedon or the bus is reset.

Then, the STB 102 transmits a response corresponding to the connectioncommand to the DTV 101 in accordance with the connection commandtransmitted from the DTV 101.

Here, the STB 102 may transmit a command identical to the connectioncommand as the response.

Also, before transmitting the connection command to the DTV 101 as theresponse, the STB 102 may additionally write the bandwidth allocatedfrom the isochronous resource manager in the bandwidth region, thechannel number allocated from the isochronous resource manager in thesource channel number region, its own output plug control register (PCR)number in the output PCR number region, the allocated channel number inthe destination channel number region, and the input PCR number of theDTV 101 in the input PCR number region, respectively.

Thereafter, the STB 102 is allocated with the channel and bandwidth fromthe isochronous resource manager (not illustrated), sets its own outputplug control register and the input plug control register of the DTV 101for the point-to-point connection as shown in FIG. 1, and then transmitsthe data stream of the program to the DTV 101 to display the data streamon the screen.

Here, the DTV 101 writes “0x10”, which means the broadcast connection,in the subfunction region of the connection command, and transmits theconnection command, so that the data stream of the program can bebroadcast from the STB 102 to not only the DTV 101 itself but also othernodes connected to the IEEE 1394 cable.

If the display is completed, the DTV 101 transmits the connectioncommand to the STB 102 after writing “0x01” in the subfunction region ofthe connection command to record the point-to-point connection, “0x10”in the connection region to record cut-off of the connection, the nodeID of the STB 102 in the source node ID region, and its own node ID inthe destination node ID region, so that the point-to-point connection orthe broadcast connection can be released.

Also, if a user selects the DVD player 103 among the DTV 101, STB 102,and DVD player 103 displayed on the screen as shown in FIG. 2 to storethe data stream of the program being viewed in the disk 104, the DTV 101transmits the connection command of a predetermined format as shown inFIGS. 3 a and 3 b to the DVD player 103 with the DVD player 103determined as a master to store the data stream.

Specifically, before transmitting the connection command to the DVDplayer 103, the DTV 101 writes “0x01” in the subfunction region of theconnection command as shown in FIGS. 3 a and 3 b to record thepoint-to-point connection, “0x00” in the connection region to record themaking of the connection, the node ID of the DTV 101 in the source nodeID region, and the node ID of the DVD player 103 in the destination nodeID region, respectively.

The node IDs of the nodes displayed on the screen are connected to theIEEE 1394 cable, and stored in the DTV 101 when the power is turned onor the bus is reset.

Then, the DVD player 103 transmits a response corresponding to theconnection command to the DTV 101 in accordance with the connectioncommand transmitted from the DTV 101.

Here, the DVD player 103 may transmit a command identical to theconnection command as the response.

Also, before transmitting the connection command to the DTV 101 as theresponse, the DVD player 103 may additionally write the bandwidthallocated from the isochronous resource manager in the bandwidth region,the channel number allocated from the isochronous resource manager inthe source channel number region, the output plug control register (PCR)number of the DTV 101 in the output PCR number region, the channelnumber allocated from the isochronous resource manager in thedestination channel number region, and its own input PCR number in theinput PCR number region, respectively.

Thereafter, the DVD player 103 is allocated with the channel andbandwidth from the isochronous resource manager (not illustrated), setsits own input plug control register and the output plug control registerof the DTV 101 for the point-to-point connection as shown in FIG. 1, andthen receives the data stream outputted from the DTV 101 to store thedata stream in the disk 104.

Here, the DTV 101 writes “0x10”, which means the broadcast connection,in the subfunction region of the connection command, and transmits theconnection command, so that the data stream of the program being viewedcan be broadcast from itself to not only the DVD player 103 but alsoother nodes connected to the IEEE 1394 cable.

If the display is completed, the DTV 101 transmits the connectioncommand to the DVD player 103 after writing “0x01” in the subfunctionregion of the connection command to record the point-to-pointconnection, “0x10” in the connection region to record cut-off of theconnection, the node ID of the DTV 101 in the source node ID region, andthe node ID of the DVD player 103 in the destination node ID region, sothat the point-to-point connection or the broadcast connection can bereleased.

Also, if a user selects the STB 102 among the DTV 101, STB 102, and DVDplayer 103 displayed on the screen as shown in FIG. 2 to store the datastream of the program being received from the STB 102 through the IEEE1394 cable in the disk 104, the DTV 101 transmits the connection commandof a predetermined format as shown in FIGS. 3 a and 3 b to the STB 102with the STB 102 determined as a master to store the data stream.

Specifically, before transmitting the connection command to the STB 102,the DTV 101 writes “0x01” in the subfunction region of the connectioncommand as shown in FIGS. 3 a and 3 b to record the point-to-pointconnection, “0x00” in the connection region to record the making of theconnection, the node ID of the STB 102 in the source node ID region, andthe node ID of the DVD player 103 in the destination node ID region,respectively.

The node IDs of the nodes displayed on the screen are connected to theIEEE 1394 cable, and stored in the DTV 101 when the power is turned onor the bus is reset.

Then, the STB 102 transmits a response corresponding to the connectioncommand to the DTV 101 in accordance with the connection commandtransmitted from the DTV 101.

Here, the STB 102 may transmit a command identical to the connectioncommand as the response.

Also, before transmitting the connection command to the DTV 101 as theresponse, the STB 102 may additionally write the bandwidth allocatedfrom the isochronous resource manager in the bandwidth region, thechannel number allocated from the isochronous resource manager in thesource channel number region, its own output plug control register (PCR)number in the output PCR number region, the allocated channel number inthe destination channel number region, and the input PCR number of theDVD player 103 in the input PCR number region, respectively.

Thereafter, the STB 102 is allocated with the channel and bandwidth fromthe isochronous resource manager (not illustrated), sets its own outputplug control register and the input plug control register of the DVDplayer 103 for the point-to-point connection as shown in FIG. 1, andthen transmits the received data stream to the DVD player 103.

Then, the DVD player 103 stores in the disk 104 the data stream of theprogram transmitted from the STB 102 through the point-to-pointconnection.

Here, the DTV 101 writes “0x10”, which means the broadcast connection,in the subfunction region of the connection command, and transmits theconnection command, so that the data stream of the program received fromthe STB 102 is not only stored in the disk 104 through the DVD player103 but also broadcast to other nodes connected to the IEEE 1394 cable.

If the display is completed, the DTV 101 transmits the connectioncommand to the STB 102 after writing “0x01” in the subfunction region ofthe connection command to record the point-to-point connection, “0x10”in the connection region to record cut-off of the connection, the nodeID of the STB 102 in the source node ID region, and the node ID of theDVD player 103 in the destination node ID region, so that thepoint-to-point connection or the broadcast connection can be released.

Meanwhile, if a user selects the DVD player 103 among the DTV 101, STB102, and DVD player 103 displayed on the screen as shown in FIG. 2 toreproduce through the DVD player 103 and view through the DTV 101 thedata stream of the program stored in the disk 104, the DTV 101 transmitsthe connection command of a predetermined format as shown in FIGS. 3 aand 3 b to the DVD player 103 with the DVD player 103 determined as amaster to reproduce the data stream of the program stored in the disk104 and transmit the data stream to the DTV 101 itself.

Specifically, before transmitting the connection command to the DVDplayer 103, the DTV 101 writes “0x01” in the subfunction region of theconnection command as shown in FIGS. 3 a and 3 b to record thepoint-to-point connection, “0x00” in the connection region to record themaking of the connection, the node ID of the DVD player 103 in thesource node ID region, and its own node ID in the destination node IDregion, respectively.

The node IDs of the nodes displayed on the screen are connected to theIEEE 1394 cable, and stored in the DTV 101 when the power is turned onor the bus is reset.

Then, the DVD player 103 transmits a response corresponding to theconnection command to the DTV 101 in accordance with the connectioncommand transmitted from the DTV 101.

Here, the DVD player 103 may transmit a command identical to theconnection command as the response.

Also, before transmitting the connection command to the DTV 101 as theresponse, the DVD player 103 may additionally write the bandwidthallocated from the isochronous resource manager in the bandwidth region,the channel number allocated from the isochronous resource manager inthe source channel number region, its own output plug control register(PCR) number in the output PCR number region, the allocated channelnumber in the destination channel number region, and the input PCRnumber of the DTV 101 in the input PCR number region, respectively.

Thereafter, the DVD player 103 is allocated with the channel andbandwidth from the isochronous resource manager, sets its own outputplug control register and the input plug control register of the DTV 101for the point-to-point connection as shown in FIG. 1, and thenreproduces the data stream of the program stored in the disk 104 totransmit the reproduced data stream to the DTV 101.

Then, the DTV 101 displays on the screen the data stream of the programtransmitted from the DVD player 103 through the point-to-pointconnection.

Here, the DTV 101 writes “0x10”, which means the broadcast connection,in the subfunction region of the connection command, and transmits theconnection command, so that the data stream of the program beingreproduced and transmitted from the DVD player 103 can be not onlydisplayed on the screen but also broadcast to other players connected tothe IEEE 1394 cable.

If the display is completed, the DTV 101 transmits the connectioncommand to the DVD player 103 after writing “0x01” in the subfunctionregion of the connection command to record the point-to-pointconnection, “0x10” in the connection region to record cut-off of theconnection, the node ID of the DVD player 103 in the source node IDregion, and its own node ID in the destination node ID region, so thatthe point-to-point connection or the broadcast connection can bereleased.

As described above, according to the method of controlling connectionbetween nodes in a digital interface, one node among nodes connected tothe digital interface, that is a master, determines another node to bethe master, and controls a point-to-point connection or a broadcastconnection among the nodes, so that the transmission/reception,reproduction, and control of the data stream of a certain program can besmoothly performed.

While the present invention has been described and illustrated hereinwith reference to the preferred embodiments thereof, it will be apparentto those skilled in the art that various modifications and variationscan be made therein without departing from the spirit and scope of theinvention. Thus, it is intended that the present invention covers themodifications and variations of this invention that come within thescope of the appended claims and their equivalents.

1. A method for controlling a connection through a serial bus,comprising: receiving a control command that identifies a destinationnode and describes a requested state of the connection, from a sourcenode, the requested state of connection including a command indicatingwhether the destination node is operated to be connected or disconnectedwith the serial bus; and transmitting, based on receiving the controlcommand, a response command describing a current state of theconnection, to the source node, the response command includingidentification information of the source node.
 2. The method of claim 1,wherein the control command is received at the destination node, andwherein the response command is transmitted from the destination node.3. The method of claim 1, wherein the control command identifies thedestination node using a unique node identifier.
 4. The method of claim3, wherein the unique node identifier is a unique physical nodeidentifier.
 5. The method of claim 1, wherein the requested state ofconnection comprises an enabled port connection state, a disabled portconnection state, a connected connection state, or a disconnectedconnection state.
 6. The method of claim 1, wherein the control commandor the response command comprise preformatted commands.
 7. The method ofclaim 1, wherein the destination node is a digital versatile disc (DVD)player, a digital television (DTV), or a set-top box (STB).
 8. A devicefor controlling a connection through a serial bus, comprising: means forreceiving a control command that identifies a destination node anddescribes a requested state of the connection, from a source node, therequested state of connection including a command indicating whether thedestination node is operated to be connected or disconnected with theserial bus; and means for transmitting, based on receiving the controlcommand, a response command describing a current state of theconnection, to the source node, the response command includingidentification information of the source node.
 9. A device forcontrolling a connection through a serial bus, comprising a master plugregister configured to: receive a control command that identifies adestination node and describes a requested state of the connection, froma source node, the requested state of connection including a commandindicating whether the destination node is operated to be connected ordisconnected with the serial bus; and transmit, based on receiving thecontrol command, a response command describing a current state of theconnection, to the source node, the response command includingidentification information of the source node.